British American Tobacco PLC, maker of Kent and Dunhill cigarettes, is the world’s No. 2 cigarette maker by sales after Altria Group Inc. and is inextricably linked to any deal. BAT owns a 42% stake in Reynolds and would have a say in the outcome of any combination with Lorillard.

Next in line is Imperial Tobacco Group PLC, the No. 4 global tobacco company, currently with around a 3% share of the U.S. tobacco market. Imperial is looking to grow in the U.S. and will eagerly await the outcome of the Reynolds-Lorillard talks.

For BAT, there are three primary options should the deal happen and one fantasy move that would turn the global tobacco industry on its head.

Do nothing: BAT would then see its stake dilute in the enlarged company but still retain part of a company selling Newport, Camel and Pall Mall cigarettes.

Up its stake: BAT could seek to buy more shares in the new company, thus increasing its exposure in the U.S. “We think it would be advantageous [for BAT] to increase its stake in the combined company,” wrote analysts Adam Spielman and Pooja Shirangi of Citi in a research note published Wednesday.

Sell out: BAT could sell its 42% holding in Reynolds, either directly to Reynolds before a deal with Lorillard is done; or after, to the new company.

Buy the whole thing: With a combined market value of $55 billion at Wednesday’s closing prices, BAT would be stretched to buy a merged Reynolds and Lorillard, but it could happen. “BAT has the cash to buy Reynolds outright as it stands” but would need some help to buy the combined company, said James Edwardes Jones, managing director at RBC Capital Markets.

Whatever happens, Imperial could stand to benefit, according to the analysts at Citi. “If such a combined entity were formed it will likely need to sell assets for antitrust reasons, and we think Imperial could be a potential buyer,” the analysts said.

Both Imperial and BAT shares were up strongly in London trading.

A spokeswoman for BAT and a spokesman for Imperial declined to comment on speculation.